1. Field of the Invention
The present invention generally relates to a power distribution or transmission device, in particular, to a power distribution device used in a server rack system.
2. Description of Related Art
A server is a core computer serving the other computers in a network system, which may provide functions such as a magnetic disk and a print service required by a network user, and may also enable clients to share resources in a network environment with each other. The basic architecture of the server is generally the same as a common personal computer, and is formed of components such as a Central Processing Unit (CPU), a memory and an Input/Output (I/O) apparatus, which are connected by a bus therein. The CPU is connected to the memory through a north bridge chip, and the I/O apparatus is connected through a south bridge chip. The server has experienced about three evolution processes according to the structure of a chassis: from an early tower chassis to a rack mode emphasizing centralized performance, and then to a blade server with a high-density computation approach.
Here, a rack server is taken as an example. The rack server is a server with an appearance designed according to a unified standard and used in cooperation with a cabinet. The rack server may be regarded as a tower server with an optimized structure, and is designed mainly to reduce the space occupation of the server as much as possible. Many professional network apparatuses use the rack structure in a flat type mostly, just like a drawer, such as an exchanger, a router, or a hardware firewall. The width of the rack server is 19 inches, and the height thereof uses U as a unit (1 U=1.75 inches=44.45 millimeters). Generally, 1U, 2U, 3U, 4U, 5U and 7U servers exist.
Generally speaking, server units (for example, the exchanger, the router and the hardware firewall) located in the rack are connected to a power supply through cables, and are uniformly powered by the power supply. However, in such a configuration, additional space is needed for placing the cables in the rack and to facilitate movement of the cables with the chassis when withdrawing the server units. This reduces the utilization efficiency of the rack. Moreover, as the number of server units increases, the number of cables also increases, making assembly and service of the server units more complex, error prone, and time consuming.